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Re: Re.: If Dinosaurs Could Fly and an old 'axiom'



Could be I'm missing something in all this, 'Which came first, the down or the (flight) feathers?' controversy; but as a simple neophyte in all this, it seems to me certain persons have forgotten a long-held axiom of comparative anatomy: ONTOGENY RECAPITULATES PHYLOGENY.
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It isn't forgotten - merely disproved. This "axiom" simply has too many exceptions to be regarded as any sort of evidentiary rule today.
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In regard of this, if flight feathers came first (from scales or however), then how is it that all the hundreds of baby chicks I ever watched in a farm town while growing up in south Texas always hatched with 'DOWN FEATHERS' as the first covering, only after which appeared the 'FLIGHT FEATHERS'?
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Probably because thermoregulation is much more important to newly-hatched chicks than flight. Hatchling megapodes (fowl-like birds from Australasia) can fly and do have flight feathers that develop at roughly the same time as their first body feathers. The point is that this is probably an adaptive mechanism, not evolutionary recapitulation.



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Ronald I. Orenstein Phone: (905) 820-7886
International Wildlife Coalition Fax/Modem: (905) 569-0116
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